Worm drive circular saw

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Hi guys, what's the difference between a worm drive circular saw and a regular circular saw, besides the price?
Reply:The older ones had a larger dia blade that would cut a 4x4. Plus the blade is normally on the oposite side of a circ saw. My buddy says its so you can see better...BobBob WrightSalem, Ohio  Birthplace of the Silver & Deming Drillhttp://groups.yahoo.com/group/southbend10k/http://groups.yahoo.com/group/sawking/1999 Miller MM185 w/ Miller 185 Spoolmate spoolgun
Reply:Regular circular saws are direct drive. A worm drive is exactly that. The motor drives a worm gear that transfers the power to the blade. Because of this a worm drive has more torque and will cut when a direct drive saw would stall out. When you hit the trigger, you'll feel that saw twist if you are holding it one handed in mid air, because of all the torque generated by the motor. Because of the torque, they use diamond knock outs in the blades rather than the standard round arbor. Also the motors are heavier. Most are13 or 15 amp. It's not at all uncommon for a worm drive to trip a 15 amp breaker doing a heavy cut.I have 4. Two 7 /14" ones ( one dedicated to cutting concrete) , one 8 1/4", and one 10". I wished I had grabbed the 16" one when the store down the street was closing. That one cuts 6x6's in one pass, 4x4's at 45 deg.Oh one other thing. the blades on the oposite side compared to most standard saws. Thats so a right handed guy running the saw can see the blade and guide marks useing it in his right hand, while the left holds the material. All my saws are that way, my standard "trim" saw is a Porter Cable thatsgot the blade on the same side as the worm drives. Lots of people can't get used to that, but after a bit you'll wonder why all the others are backwards.Last edited by DSW; 12-20-2009 at 12:14 PM..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I have the Skil HD77.  It's a beast and keeps on cutting regardless of load.   Dad has the Skil Mag77 he uses in his handyman business.  The Mag is the same saw as the HD, but with a lighter weight magnesium case.  That's a nice saw.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:I've seen the diamond knockouts on my sawblades, but never have seen a saw that took them.
Reply:Another point, the straight gear saws use Spur and Helical gears. Spur gears whine at high speed and loads, and tend to break more easily. Helical gears run smoothly and quietly. Cut lumber all day with a Spur gear saw and by days end your ears will be ringing.
Reply:I recently made a saw horse out of (of course) steel. The top is a piece of 4 inch C channel with the channel facing upwards.Yesterday I was cutting a piece of plywood on this horse with my skill 77HD worm drive. I had the plywood position in-correctly, and cut right through the top of the 4 in C channel and would not have noticed it except for the steel shavings coming up through the board . the saw did not even slow down.I have also used it to cut sections of sidewalk out for drainage and many other things that would stall a conventional circular saw.These worm drive saws are monsters....highly recommended.RMiller 302GMIller 12RC SuitecaseMIller 30A spoolgunHF-251D-1WP17 Tig torchSmith HD torchHypertherm 45Jet drill pressHF 7X12 wet cut horizontal band sawPlasmacam CNC table
Reply:Worm-drive circular saws use worm-drive gears to get the motion from the electric motor to the blade.Because of that gearing arrangement, the motor is 'behind' the blade and the physical proportions of the whole saw are kind of long and thin. Also, the blade is typically on the left side of the saw and thus a 'righty' has a better view of the blade and the cut-line than when the blade is on the right side of the saw.Most worm-drive saws also have a slightly reduced blade rpm than on a 'comparable' helical-drive saw.  With a comparable electric motor on both types of saws, that means that there is a little bit more torque at the blade of the worm-drive saw.  Power = torque x rpm   For a standard 7-1/4 inch circular saw, worm-drive saws usually run 4400-4600 rpm and helical-drive saws run 5000-5800 rpm.http://boschtools.com/Products/Tools...aspx?pid=1677Mhttp://boschtools.com/Products/Tools....aspx?pid=CS10Regarding which side of the saw the blade is on, some brands also make a helical-drive saw with the blade on the left side too.http://boschtools.com/Products/Tools...l.aspx?pid=CS5  (6200 rpm! )Helical or spur drive saws have the motor hanging off to the side of the saw (as opposed to the worm-drive saw having the motor 'in-line' and behind the blade) and thus are a bit wider and have a different balance than a worm-drive saw.  Most helical-drive saws have a higher blade rpm than most worm-drive saws, but not always.  http://www.dewalt.com/us/products/to...?categoryID=85Notice the specs on the DW378 saw.  Helical-drive, left-side blade and 4600 rpm.http://www.dewalt.com/us/products/to...?productID=135DSW, no circular saw that I know of is direct drive.  They all use gears between the motor and the blade.  But yes, since most worm-drive saws run a lower blade rpm than most helical-drive saws the torque at the blade is higher for the worm-drive saw than for a comparable helical-drive saw.  See above about Power = torque x rpm  So with the same/comparable power from the motor, if the blade rpm is higher there is less torque at the blade and if the blade rpm is lower then there is more torque at the blade.  If some company did make a direct-drive saw and connected say a 3600 rpm 15 amp electric motor to the blade with no gearing between the blade and the motor, then that saw would have more torque at the blade than the saw motor running through any speed-increasing gearing.  As well as not having any efficiency losses from the gearing.Back to the original question.  Most worm-drive saws are of the 'heavy-duty' variety, but only -some- of the helical-gear saws are of the heavy-duty variety.  Some of the helical-gear saws are pretty darn wimpy compared to the heavy-duty saws.  But the heavy-duty helicals are pretty much just as heavy-duty as the worm-drive saws.Worm-drive saws usually have replaceable gear lube.  Helical (or spur gear) saws usually don't.  If you -don't- have (because the lube leaked out maybe) or replace the lube in a worm dirve, you ruin the gears.  YMMV.http://www.skiltools.com/en/AllTools...lt.html?cid=45  The best laid schemes ... Gang oft agley ...
Reply:Worm drive saws have their motor perpendicular to the blade shaft and the others have the motor parallel to the blade shaft. That's the only real difference. Blade being on left or right is dependant on manufacturer. Diamond knockouts are used on most high end saws reguardless of type.
Reply:Originally Posted by highplainsdrifterI recently made a saw horse out of (of course) steel. The top is a piece of 4 inch C channel with the channel facing upwards.Yesterday I was cutting a piece of plywood on this horse with my skill 77HD worm drive. I had the plywood position in-correctly, and cut right through the top of the 4 in C channel and would not have noticed it except for the steel shavings coming up through the board . the saw did not even slow down.I have also used it to cut sections of sidewalk out for drainage and many other things that would stall a conventional circular saw.These worm drive saws are monsters....highly recommended.R
Reply:Originally Posted by DSWLots of people can't get used to that, but after a bit you'll wonder why all the others are backwards.
Reply:Originally Posted by DSW Boss needed to rip a couple 2x's fast one day, so he clamped it to the step bumper of the work truck and went at it with the worm drive. He was Btch'n about a dull blade after the first one. Loading the truck later I noticed several shinny grooves in the top of the pintle hitch about 3/16" deep. Powered right thru the 2x and hitch top and didn't even slow down.